Hepatitis B Mutations Predict Liver Cancer

A specific double mutation in the hepatitis B virus (HBV) could be a biomarker for predicting the development of hepatocellular carcinoma, a type of liver cancer, in people infected with the virus, according to researchers at the Johns Hopkins Bloomberg School of Public Health and the People’s Republic of China. The investigators identified the HBV mutations in tumors from liver cancer patients and in the blood samples of study participants, which were taken up to 8 years before cancer was diagnosed. The researchers said the biomarker could be used as a test to predict liver cancer in cancer prevention studies. Their findings were published in the March 9, 2004, edition of the Proceedings of the National Academy of Sciences.

Hepatocellular carcinoma is a leading cancer in many parts of the world, including Asia and sub-Saharan Africa. More than 400 million people worldwide are infected with HBV, which is a major risk factor for liver cancer.

“Liver cancer is a growing problem in the world and in the United States, because of the spread of HBV,” said John Groopman, MD, PhD, senior author of the study and chair of the Department of Environmental Health Sciences at the School of Public Health. “We can use this biomarker to identify patients who may be candidates for liver cancer prevention studies.”

Dr. Groopman and his colleagues first detected the double HBV mutation, known as 1762T/1764A, in liver tumors. The patients were participants in a study examining the risk factor for hepatocellular carcinoma conducted in China’s Qidong province. The double mutation was found in 52 of the 70 tumors examined and in plasma samples from 4 of the 6 participants.

The researchers then looked at stored plasma to determine if the presence of the mutation would predict future liver cancers. They examined blood samples taken from 120 participants who had been monitored for aflatoxin and HBV exposure as part of a separate 10-year study of hepatocellular carcinoma risk factors. During the 10-year period, six of the participants developed liver disease. All had detectable levels of the HBV mutations up to 8 years before their liver disease diagnosis. Finally, the researchers expanded their study to include 15 liver cancer patients taken from a third study of 1,638 high-risk individuals. Eight of the 15 participants had detectable levels of the double mutation.

The study was funded through grants from the National Institute of Environmental Heath Sciences.

Public Affairs Media Contacts for the Johns Hopkins Bloomberg School of Public Health: Tim Parsons or Kenna Brigham at 410-955-6878 or paffairs@jhsph.edu. Photographs of Dr. Groopman are available upon request.